Conducting systematic reviews of association (etiology)

Abstract

The systematic review of evidence is the research method which underpins the traditional approach to evidence-based healthcare. There is currently no uniform methodology for conducting a systematic review of association (etiology). This study outlines and describes the Joanna Briggs Institute's approach and guidance for synthesizing evidence related to association with a predominant focus on etiology and contributes to the emerging field of systematic review methodologies. It should be noted that questions of association typically address etiological or prognostic issues.The systematic review of studies to answer questions of etiology follows the same basic principles of systematic review of other types of data. An a priori protocol must inform the conduct of the systematic review, comprehensive searching must be performed and critical appraisal of retrieved studies must be carried out.The overarching objective of systematic reviews of etiology is to identify and synthesize the best available evidence on the factors of interest that are associated with a particular disease or outcome. The traditional PICO (population, interventions, comparators and outcomes) format for systematic reviews of effects does not align with questions relating to etiology. A systematic review of etiology should include the following aspects: population, exposure of interest (independent variable) and outcome (dependent variable).Studies of etiology are predominantly explanatory or predictive. The objective of reviews of explanatory or predictive studies is to contribute to, and improve our understanding of, the relationship of health-related events or outcomes by examining the association between variables. When interpreting possible associations between variables based on observational study data, caution must be exercised due to the likely presence of confounding variables or moderators that may impact on the results.As with all systematic reviews, there are various approaches to present the results, including a narrative, graphical or tabular summary, or meta-analysis. When meta-analysis is not possible, a set of alternative methods for synthesizing research is available. On the basis of the research question and objectives, narrative, tabular and/or visual approaches can be used for data synthesis. There are some special considerations when conducting meta-analysis for questions related to risk and correlation. These include, but are not limited to, causal inference.Systematic review and meta-analysis of studies related to etiology is an emerging methodology in the field of evidence synthesis. These reviews can provide useful information for healthcare professionals and policymakers on the burden of disease. The standardized Joanna Briggs Institute approach offers a rigorous and transparent method to conduct reviews of etiology.

The association of overjet size and traumatic dental injuries—A systematic review and meta‐analysis

“…There is currently no universally accepted methodology for conducting systematic reviews of etiology and risk. The review protocol was approved by the JBI and hence followed its guidelines in order to ensure a robust methodology. The review aimed to synthesize the best available evidence by only including high methodological quality studies as they “provide scientifically sound and clinically relevant results.” This, in turn, ensures that the review's results are reliable and valid.…”

“…The title and protocol of this systematic review were registered a priori with the Joanna Briggs Institute (JBI) and PROSPERO (CRD42017060907). The protocol was peer reviewed, approved, and published by the JBI, and followed their guidelines for a systematic review of association (etiology) methodology . The JBI methodology was adopted over other methodologies as it has a “broader definition of what constitutes research evidence for practice.” Furthermore, systematic reviews of etiological studies are “important in the public health domain for informing healthcare planning, resource allocation, and strategies for disease prevention.” The JBI approach “aims to integrate the richness of the qualitative traditions in order to capture the whole phenomenon of interest.” The specific review question was: what is the relationship between overjet size and risk of developing a TDI in the primary, mixed, and secondary dentitions?…”

“…Reviews of association (etiology) follow Population, Exposure, and Outcome when identifying criteria for inclusion . “The usual population, intervention, comparator, and outcome (PICO) approach to generate review questions for systematic reviews does not align with reviews related to etiology.” Studies of healthy human participants of any age and in any dental dentition stage were considered for inclusion.…”

Systematic literature review on the delays in the diagnosis and misdiagnosis of cluster headache

“…Quality assessment was performed using the Joanna Briggs Institute (JBI) Appraisal Checklist for case series studies [8]. Ten domains of the study design and reporting were assessed, each rated ‘Yes’, ‘No’, ‘Unclear’ or ‘Not applicable’.…”

Inadequate diversity of information resources searched in US-affiliated systematic reviews and meta-analyses: 2005–2016

“…A study was considered to have studied safety if any outcome studied satisfied the definition of harms as in PRISMA-Harms guidelines for SRMAs (encompassing various terms such as “adverse drug reaction,” “adverse effect,” “adverse event,” “complication,” “harm,” “safety,” “side effect,” and “toxicity”) [38]. Studies were deemed having other outcomes as per their established definitions in context of SRMAs (eg, diagnostic [39], prognostic [40], epidemiological (etiological/descriptive/association) [41–43], economic analysis [44]). A single SRMA could have multiple types of outcomes.…”